diff --git a/src/core/CL/cl_kernels/reduction_operation.cl b/src/core/CL/cl_kernels/reduction_operation.cl
index a5fd0b3..b9d33bd 100644
--- a/src/core/CL/cl_kernels/reduction_operation.cl
+++ b/src/core/CL/cl_kernels/reduction_operation.cl
@@ -196,7 +196,7 @@
 #if defined(MIN)
         res = select(res, in, CONVERT(ISLESS(in, res), COND_DATA_TYPE));
 #elif defined(MAX)
-        res                             = select(res, in, CONVERT(ISGREATER(in, res), COND_DATA_TYPE));
+        res = select(res, in, CONVERT(ISGREATER(in, res), COND_DATA_TYPE));
 #elif defined(PROD)
 #if defined(OFFSET) && defined(SCALE)
         res_f *= DEQUANTIZE(in, OFFSET, SCALE, DATA_TYPE_PROMOTED, 1);
@@ -223,11 +223,7 @@
     res = QUANTIZE(res_f, OFFSET, SCALE, DATA_TYPE_PROMOTED, 1);
 #endif // defined(PROD) && defined(OFFSET) && defined(SCALE)
 
-#if defined(MIN) || defined(MAX)
-    *((__global DATA_TYPE_PROMOTED *)output.ptr) = res;
-#else  // !(defined(MIN) || defined(MAX))
     *((__global DATA_TYPE *)output.ptr) = CONVERT_SAT(res, DATA_TYPE);
-#endif // defined(MIN) || defined(MAX)
 }
 #endif // defined(WIDTH)
 
@@ -276,7 +272,7 @@
 #if defined(MIN)
         res = select(res, in, ISLESS(in, res));
 #elif defined(MAX)
-        res                             = select(res, in, ISGREATER(in, res));
+        res = select(res, in, ISGREATER(in, res));
 #else // !(defined(MAX) || defined(MIN))
 #if defined(SUM_SQUARE)
         in *= in;
@@ -373,7 +369,7 @@
 #if defined(MIN)
         res = select(res, in, ISLESS(in, res));
 #elif defined(MAX)
-        res                             = select(res, in, ISGREATER(in, res));
+        res = select(res, in, ISGREATER(in, res));
 #else // !(defined(MAX) || defined(MIN))
 #if defined(SUM_SQUARE)
         in *= in;
@@ -472,7 +468,7 @@
 #if defined(MIN)
         res = select(res, in, ISLESS(in, res));
 #elif defined(MAX)
-        res                             = select(res, in, ISGREATER(in, res));
+        res = select(res, in, ISGREATER(in, res));
 #else // !(defined(MAX) || defined(MIN))
 #if defined(SUM_SQUARE)
         in *= in;
diff --git a/src/core/CL/kernels/CLReductionOperationKernel.cpp b/src/core/CL/kernels/CLReductionOperationKernel.cpp
index ff824fc..a0f9a49 100644
--- a/src/core/CL/kernels/CLReductionOperationKernel.cpp
+++ b/src/core/CL/kernels/CLReductionOperationKernel.cpp
@@ -87,14 +87,7 @@
     {
         case 0:
         {
-            if(is_serial_op)
-            {
-                AccessWindowHorizontal input_access(input, 0, input->dimension(0));
-                AccessWindowHorizontal output_access(output, 0, 1);
-                window_changed = update_window_and_padding(win, input_access, output_access);
-                output_access.set_valid_region(win, ValidRegion(Coordinates(), output->tensor_shape()));
-            }
-            else
+            if(!is_serial_op)
             {
                 const unsigned int     border_width = ((input->dimension(0) % border_val) != 0) ? border_val - input->dimension(0) % border_val : 0;
                 AccessWindowStatic     input_access(input, 0, 0, input->dimension(0) + border_width, 1);
@@ -269,8 +262,11 @@
                 Window window_in{ window };
                 window_in.set(Window::DimX, Window::Dimension(0, _input->info()->dimension(0), _input->info()->dimension(0)));
 
-                Window in_slice  = window.first_slice_window_1D();
-                Window out_slice = window.first_slice_window_1D();
+                Window out_window{ window };
+                out_window.set(Window::DimX, Window::Dimension(0, 0, 0));
+
+                Window in_slice  = window_in.first_slice_window_1D();
+                Window out_slice = out_window.first_slice_window_1D();
 
                 do
                 {
@@ -279,7 +275,7 @@
                     add_1D_tensor_argument(idx, _output, out_slice);
                     enqueue(queue, *this, in_slice, lws_hint());
                 }
-                while(window_in.slide_window_slice_1D(in_slice) && window.slide_window_slice_1D(out_slice));
+                while(window_in.slide_window_slice_1D(in_slice) && out_window.slide_window_slice_1D(out_slice));
             }
             else
             {